1. Field of the Invention
The present invention relates to a damping apparatus restraining vibration transfer between objects.
2. Description of the Related Art
In general, as shown in FIG. 1, a damping apparatus 10 is installed between two objects 11 and 12 to restrain vibration transfer between the two objects. The conventional damping apparatus is comprised of a rubber member 13 for absorbing vibration, and lower and upper plates 14 and 15 made of steel and joined to the lower and upper ends of the rubber member 13, respectively, by adhesive bonding or insert molding. Threaded portions 14a and 15a are provided at the lower and upper plates 14 and 15, respectively. After the threaded portions 14a and 15a are inserted through the through-holes 11a and 12a, nuts 16 and 17 are tightened to fix the damping apparatus 10 between the two objects 11 and 12. After assembly, the rubber member 13 buffers a vibration generated by either of the objects 11 and 12 to lessen vibration transfer between the objects.
In joining the damping apparatus 10 to the two objects 11 and 12, another method is employed in addition to the above-mentioned method in which the nuts 16 and 17 are fitted around the threaded portions 14a and 15a and tightened. Alternatively, a threaded hole 14a′ is provided at one plate, for example, the lower plate 14, and a bolt 16′ is screwed to fasten the object 11 to the damping apparatus 10 as shown in FIG. 2.
However, in both of these structures, drawbacks include that the processes of manufacturing and installing the damping apparatus are very troublesome. That is, for example, in the damping apparatus 10 shown in FIG. 1, first, the lower and upper plates 14 and 15 are made by press stamping or casting. Then, the plates 14 and 15 are provided with respective through holes, and the threaded portions 14a and 15a are assembled to the respective plates 14 and 15. Thereafter, the rubber member 13 is attached to the assembled plates 14 and 15 with an adhesive, or is joined to the assembled plates 14 and 15 by insert molding. Since the conventional damping apparatus 10 is manufactured as described above, the manufacturing process thereof is troublesome.
Further, in the installing process of the damping apparatus 10, the damping apparatus 10 is disposed on the first object 11, and the threaded portion 14a and the nut 16 are firmly joined. Then, the second object 12 is disposed on the damping apparatus 10, and the threaded portion 15a and the nut 17 are firmly joined. Since the installing process requires multiple assembling steps as described above, the installing process is not as simple as desired. Further, from a view of material management, or manufacturing cost, it is not preferable that separate joining members, such as the nuts 16 and 17 and the bolt 16′, must be separately prepared and used.
Therefore, a damping apparatus having an improved structure is required to overcome these drawbacks, among others.